In addition to what has been said, I'd like to see you do something totally unique and different than the other thousands of jewelry sellers. Seek out unique materials, research and hone your skills.
For example, I think most earrings have head pins instead of eye pins on the end of beads and have the same color of metal throughout. This would make your jewelry appear more professional...unless you are purposefully going for that look. When I first started I used what I had available instead of going out to buy the correct materials but as I sold things I put that money back into my shop to improve the quality. Still working on this, finding the perfect chain is my newest mission!
Best wishes, Lori